DR-SDSN: An Elastic Differentiated Routing Framework for Software-Defined Satellite Networks

Software-defined satellite networking (SDSN) has recently gained unprecedented attention due to its great controllability for traffic delivery. However, it is still facing several fundamental challenges in routing, which mainly involves effective network maintenance, heterogeneous network convergence, and customized flow steering. Hence, in this article, we propose an elastic routing framework for SDSN, aiming to first build a robust control path for signalling exchanges, then offer a transparent channel for IP services based on Loc/ID mappings and associated encapsulations, and finally enable hybrid packet forwarding manners to meet user various demands. Moreover, we define a new 8 B network header for DR-SDSN to further decrease overheads in packet encapsulations, where 16-bit addresses are used instead of 32-bit IPv4 and 128-bit IPv6 addresses. At last, we have implemented a corresponding proof-of-concept prototype with the modified Ryu and OvS, and the Linux socket application programming interface is also extended to handle our protocol with 16-bit addresses. Extensive evaluations are performed and associated results have confirmed the feasibility and advantages of the proposed DR-SDSN framework.